1. Field of the Invention
This invention relates generally to the field of geophysical prospecting and more particularly to apparatus for generating seismic waves in the earth adaptable for use in a marshy or wetlands environment.
2. Description of the Prior Art
The transitional area between ground solid enough to support land-based impulsive and vibratory seismic sources and open water of depth sufficient for airguns has long been a challenge for seismic data acquisition. Recently it has become even more so with increased emphasis on natural environment preservation. The present invention is designed to extend the capabilities of existing impulsive sources in order to meet the needs of marsh land operations.
For the purposes of the description of this invention to follow and the appendant claims the terms "marsh land," "swamp," or "marshy environment" are understood to mean, more or less interchangeably, a coastal or other wet flat land covered with water or soft mud wherein vegetation may be really more important than open water and wherein there may be a complete lack of solid foundation. The term "swamp buggy" as used herein and in the claims is intended to refer to an automotive vehicle well known to the art for traveling or navigating over terrain characterized by marsh lands or swamps, and especially, although not limited to, such a vehicle provided with very large tires for flotation and for propulsion and which is suitable for amphibious operation. Finally, the term "fluid" as used herein and in the claims is intended to mean any nongaseous medium ranging in consistency from open water to flowable mud.
The preferred form of the invention to be described, utilizes an impulsive seismic source of the type described generally in U.S. Pat. No. 4,284,165 entitled "Acoustic Pulse Generator" issued on Aug. 18, 1981 to Tom P. Airhart et al, the content of which are incorporated herein by reference. However, as will become apparent from what follows, other forms of impulsive source wherein a mass is propelled against a target member may be employed in constructing and practicing this invention.
The general object of the invention is to provide an improved seismic source for operation in a marshy environment
More particularly, the invention has as its object the provision of vehicle mounted apparatus utilizing an impulsive seismic source capable of operations in such an environment.
Other and further objects and advantages of the invention will become apparent from a consideration of the detailed description to follow taken in conjunction with the accompanying drawings and appended claims.